Electric heater



United States Patent ELECTRIC HEATER NJ., assignor to The Oiljak Montcl'air, N.J., a corpora- George Persak, Jr., Verona, Manufacturing Co., Inc., tion of New Jersey The invention herein disclosed relates to electric heaters, particularly of the portable type.

Objects of the invention are to provide an efiicient economical heater of compact design and light weight and thereby adapted to be shifted about and placed where heat is desired and which in a simple, durable construction will create and maintain circulation of air over the full heating surface of the unit, thus to furnish maximum heat and effective distribution of that heat both by radiation and convection.

The novel features of construction, combination and relation of parts by which such results are attained are set forth and will appear in the course of the following specification.

The drawing accompanying and forming part of the specification is illustrative of a present commercial embodiment of the invention but it will be understood that structure may be modified and changed as regards the immediate illustration, all within the true intent and scope of the invention as hereinafter defined and claimed.

Fig. l of the drawing is a front elevation of one of the heaters, partly broken away for lack of space.

Fig. 2 is an end view of the heater.

Fig. 3 is an enlarged broken vertical sectional view through the body of the heater on substantially the plane of line 33 of Fig. l with arrows indicating flow of air up over opposite faces of the heating element created by the structure.

Fig. 4 is a broken horizontal sectional view on substantially the plane of line 4-4 of Fig. 1.

Fig. 5 is a broken plan of a portion of one of the cover plates showing how it is notched in the edge to enable folding of the plate to create the air-flow chimney forming passages.

Fig. 6 is a similar view showing the plate folded or corrugated to bend up the hollow fins forming the passages.

Figs. 1 and 2 show how the heater may be made up in a relatively thin panel, extended horizontally and vertically in any desired dimensions and arranged to radiate and distribute heat from both extended surfaces of the same.

In the illustration the heating element is a thin, flat sheet 7 of impregnated canvas, glass fibre panel or other such known heater element of this thin flat character.

This thin flat heating pad 7 is sandwiched between layers 8 of paper or other suitable insulation and over these sheets of insulation, sheet metal cover plates 9 are applied.

The latter are of special construction, having spaced corrugations extending vertically between their upper and lower edges forming hollow outstanding ribs 10 providing vertical air passages 11 open at upper and lower ends to promote vertical convection air currents over the opposite faces of the heater panel.

Figs. 5 and 6 show how these channel forming corrugations may be produced by cutting the upper and lower edges of the plates in wide notches 12, extended ice at the inner ends into deeper cuts 13 and then folding the material left inwardly of the notches on center lines 14 and side fold lines 15, 16 until this contracting move ment brings the opposed cut edges 17 of the notches together into abutting engagement as in Fig. 6.

This leaves the corrugated sheets with plain flat marginal strip portions 18 above and below the upper and lower ends of the chimney forming corrugations.

The corrugated cover plates are bound together in flat engagement over opposite faces of the heater grid or panel by inverted U-shaped frames 19, secured together by through-bolts 20. These U frames are shown as bent up out of tubular square cross section stock, with the lower ends spread apart as at 21, Fig. 2, to form supporting feet for the heater.

The open sides at the bottom of the U frames are shown closed by straight bar lengths 22 of the tubing secured in clamping relation over the lower edge portions of the cover plates by through-bolts 23.

An inverted U-shaped finish strip 24 is shown interposed between the side frames 19, this strip, as in Figs. 3 and 4, being of T-shaped cross section with a head portion 25 bridging and covering the space between the side frames 19 and a dependent portion 26 serving as a spacer between those frames. With this construction the screws securing the side frames may be set up as tight as necessary without imposing any strain or load on the electrical heating panel or the insulating sheets at opposite faces of the same.

The electrical connections for the heating panel are indicated at 27, Figs. 1 and 2. These are of any usual or conventional design suited to the purposes of the heater.

The construction disclosed consists of practically the only essential parts, the thin flat heating panel protected by sheets of insulation and covered by sheet metal plates corrugated to provide the convection air passages across the faces of the panel and held in place by side frames, extended at the bottom to form floor engaging supports for the structure. This is a simple inexpensive sturdy structure, occupying but small space and providing a maximum of heat generated and distributed.

As shown in Fig. 3 the square tubing frames 19 and the chimney forming corrugations 10 project to substantially the same extent, providing a flat flush structure and with the side frames 19 and bottom bars 22 covering upper and lower ends of the air passages 11 to protect them against dust or entry of small objects but leaving lateral inlets and outlets 28 and 29 at lower and upper ends for free passage of air currents.

The invention thus utilizes the full heating capacity of the extended thin heater panel, taking off heat by radiation and convection from practically the full surface at both sides of the same. This enables the heater to be of relatively small size and thus to take up but small space in a room. While usually preferred to support the heater on the floor, it is contemplated that it may be hung from a ceiling or wall or mounted in various other ways. I

What is claimed is:

1. A heater comprising a thin fiat electric heater pad, sheet metal cover plates over opposite faces of said pad and insulated therefrom, said cover plates having flat marginal portions and vertically extending outwardly projecting corrugations between and terminating short of said flat marginal portions, said corrugations having open upper and lower ends and thereby forming open ended vertical air flues extending upwardly over the opposite faces of said heater pad, frames over said flat marginal portions of said cover plates in position covering the open ends of said air flue corrugations but spaced from said open ends to permit free flow of rising heated air through said flues and means securing the frames at opposite sides of the heater together in clamping engagement over the marginal portions of said cover plates.

2. A heater comprising a thin flat electric heater pad, sheet metal cover plates over opposite faces of said pad and insulated therefrom, said cover plates having flat marginal portions and vertically extending outwardly projecting corrugations between and terminating short of said flat marginal portions, said corrugations having open upper and lower ends and thereby forming open ended vertical air flues extending upwardly over the opposite faces of said heater pad, frames over said fiat marginal portions of said cover plates in position covering the open ends of said air flue corrugations but spaced from said open ends to permit free flow of rising heated air through said flues, means securing the frames at opposite sides of the heater together in clamping engagement over the marginal portions of said cover plates and afinish strip of substantially T-shaped cross section having the body portion of the same interposed as a spacer between said frames and marginal portions of the cover plates and having the head portion of the same extended over said frames and closing the space between said frames and marginal portions of the cover plates.

3. A heater comprising a thin flat electric heater pad,

and insulated therefrom, said cover plates having flat marginal portions and vertically extending outwardly projecting corrugations between and terminating short of' said flat marginal portions, said corrugations having open 1 upper and lower ends and thereby forming open ended sides of the heater together in clamping engagement, over the marginal portions of said cover plates, said" cover plates having aligned notches in the upper and lower edges of the same and the material intermediate aligned notches in opposite edges of the plates being sheet metal cover plates over opposite faces of said pad folded outwardly into the corrugations described forming the air flues.

References Cited in the file of this patent UNITED STATES PATENTS 1,716,459 Phelps et al. June 11, 1929 1,731,472 Murray Oct. 15, 1929 1,927,959 Soloos Sept. 26, 1933- 2,432,400 Eger Dec. 9, 1947 

